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Name Template: PUB/MISSION/level3/mmcGrd/mmcGrd_YYYY.DDD.AAA_SSSS.VVVV_nc

AAADuration (days)
DDDStarting day of year
MISSIONMission ID (eight characters or less--champ, champrt, sacc, sacctst, etc)
PUBBase directory for the pub hierarchy
SSSSSubtype (an ID which tells the command options used in generating this file)
VVVVVersion (an ID which tells the version of all codes using in generating thie file)
YYYYStarting year

A grid of averaged radio occultation data, an MMC grid, where MMC means Monthly Mean Climatology.

This file is in netCDF format (see http://www.unidata.ucar.edu/packages/netcdf/index.html) and contains one month of RO data binned into 5 degree latitude bins.

This data format was created by the RO trends study group, a group of radio occultation processing centers that have been working together to understand the benefits and limitations of different methods of processing RO data. For more details, see:

Ho, S.-P., G. Kirchengast, S. Leroy, J. Wickert, A. J. Mannucci, A. K. Steiner, D. Hunt, W. Schreiner, S. Sokolovskiy,
C. O. Ao, M. Borsche, A. von Engeln, U. Foelsche, S. Heise, B. Iijima, Y.-H. Kuo, R. Kursinski, B. Pirscher,
M. Ringer, C. Rocken, and T. Schmidt (2009),
Estimating the uncertainty of using GPS RO data for climate monitoring:
Inter-comparison of CHAMP refractivity climate records 2002-2006 from different data centers,
J. Geophys. Res., 114, D23107, doi:10.1029/2009JD011969.

Profile Data


lon

  • Description:Longitude of the center point of the bin
  • Data Type: float
  • Units: degrees_east
  • Valid Range: -180, 180
  • Missing Value: 999999

lat

  • Description:Latitude of the center point of the bin
  • Data Type: float
  • Units: degrees_north
  • Valid Range: -90, 90
  • Missing Value: 999999

altitude

  • Description:Altitude Levels: Mean sea level altitude for refractivity, dry temperature and dry pressure, Impact altitude for bending angle, Pressure altitude geopotential
  • Data Type: float
  • Units: meters
  • Valid Range: 200, 40000
  • Missing Value: 999999

time

  • Description:time
  • Data Type: float
  • Units: julian date
  • Valid Range: -180, 180
  • Missing Value: 999999

refractivity

  • Description:Refractivity
  • Data Type: float
  • Units: N-units
  • Valid Range: 0, 500
  • Missing Value: 999999

N_refractivity

  • Description:Number of averaged refractivity values
  • Data Type: short (two byte) integer
  • Units: unitless
  • Missing Value: -1

dry_temperature

  • Description:Dry Temperature
  • Data Type: float
  • Units: K
  • Missing Value: 999999

N_dry_temperature

  • Description:Number of averaged dry temperature values
  • Data Type: short (two byte) integer
  • Units: unitless
  • Missing Value: -1

dry_pressure

  • Description:Dry Pressure
  • Data Type: float
  • Units: hPa
  • Missing Value: 999999

N_dry_pressure

  • Description:Number of averaged dry pressure values
  • Data Type: short (two byte) integer
  • Units: unitless
  • Missing Value: -1

bending_angle

  • Description:Bending angle
  • Data Type: float
  • Units: radians
  • Missing Value: 999999

N_bending_angle

  • Description:Number of averaged bending angle values
  • Data Type: short (two byte) integer
  • Units: unitless
  • Missing Value: -1

geopotential

  • Description:Geopotential height
  • Data Type: float
  • Units: meters
  • Missing Value: 999999

N_geopotential

  • Description:Number of averaged geopotential height values
  • Data Type: short (two byte) integer
  • Units: unitless
  • Missing Value: -1